Reporter Jonas Elmerraji of TheStreet points in his article to the huge upfront costs:

"The acquisition of the Shaw Group made the firm one of the biggest
manufacturers of nuclear energy facilities, which carry huge upfront
construction costs in exchange for extremely low operating costs. That's
an attractive tradeoff when corporate balance sheets are stuffed but
uncertainty remains high."

Buffett is a long term investor and looks out 5-10-30 years when he takes a stock position, so we'll know if the Oracle of Omaha made a great investment one day in the distant future.

"Common
yardsticks such as dividend yield, the ratio of price to earnings or to
book value, and even growth rates have nothing to do with valuation
except to the extent they provide clues to the amount and timing of cash flows
into and from the business. Indeed, growth can destroy value if it
requires cash inputs in the early years of a project or enterprise that
exceed the discounted value of the cash that those assets will generate
in later years.Market commentators and investment managers who glibly refer to growth and value
styles as contrasting approaches to investment are displaying their
ignorance, not their sophistication. Growth is simply a
component--usually a plus, sometimes a minus-- in the value equation."